Field of the Invention
The present invention relates to metal-organic framework (MOF) materials and to methods for their manufacture. The invention has particular, but not exclusive, applicability to monolithic forms of the materials. These are of interest for various applications, including gas adsorption applications.
Related Art
Metal-organic frameworks (MOFs) are porous crystalline materials prepared by the self-assembly of metal ions and organic ligands. MOFs can have large pore volumes and apparent surface areas as high as 8,000 m2/g. MOFs combine a structural and chemical diversity that make them attractive for many potential applications, including gas storage, gas separation and purification, sensing, catalysis and drug delivery. The most striking advantage of MOFs over more traditional porous materials is the possibility to tune the host/guest interaction by choosing the appropriate building blocks, i.e. the metal ions and organic ligands, from which the MOF is formed.
WO 2010/148463 discloses a method for synthesis of MOFs in which the synthesis conditions are mild—typically below 30° C.—and the synthesis proceeds relatively quickly—typically in less than 1 hour. The synthesis takes place in a mixture of water and ethanol. The material studied in WO 2010/148463 is Cu3(BTC)2-type MOF.
Fu et al (2013) reports on efforts to incorporate a MOF (UiO-66) into a copolymer (MAA-co-EDMA) matrix, for use in liquid chromatography. The resulting structure is described as a “monolith”, and comparisons are made with a monolith formed using the copolymer only. SEM analysis shows that the microstructure of the material includes spherical MOF particles which adhere to the copolymer matrix. Huang et al (2013) provides similar disclosure.
US 2010/0181212 discloses MOF materials supported on open cell polymer foam structures, for use in gas storage applications.
Küsgens et al (2010) discloses the manufacture of Cu3(BTC)2 MOF material in situ on cordierite monolithic honeycomb structures. The results are reported to be poor. Additionally, Küsgens et al (2010) discloses the manufacture of Cu3(BTC)2-based honeycomb structures, formed by mixing Cu3(BTC)2 powder with a silicone-based binder and a methyl hydroxyl propyl cellulose plasticizer. The structures were formed by extrusion and subsequent drying at 120° C.